Buggy code:
public class IteratorUtils { public static final ResettableIterator EMPTY_ITERATOR = EmptyIterator . RESETTABLE_INSTANCE ; public static final ResettableListIterator EMPTY_LIST_ITERATOR = EmptyListIterator . RESETTABLE_INSTANCE ; public static final OrderedIterator EMPTY_ORDERED_ITERATOR = EmptyOrderedIterator . INSTANCE ; public static final MapIterator EMPTY_MAP_ITERATOR = EmptyMapIterator . INSTANCE ; public static final OrderedMapIterator EMPTY_ORDERED_MAP_ITERATOR = EmptyOrderedMapIterator . INSTANCE ; public IteratorUtils ( ) { } public static ResettableIterator emptyIterator ( ) { } public static ResettableListIterator emptyListIterator ( ) { } public static OrderedIterator emptyOrderedIterator ( ) { } public static MapIterator emptyMapIterator ( ) { } public static OrderedMapIterator emptyOrderedMapIterator ( ) { } public static ResettableIterator singletonIterator ( Object object ) { } public static ListIterator singletonListIterator ( Object object ) { } public static ResettableIterator arrayIterator ( Object [ ] array ) { } public static ResettableIterator arrayIterator ( Object array ) { } public static ResettableIterator arrayIterator ( Object [ ] array , int start ) { } public static ResettableIterator arrayIterator ( Object array , int start ) { } public static ResettableIterator arrayIterator ( Object [ ] array , int start , int end ) { } public static ResettableIterator arrayIterator ( Object array , int start , int end ) { } public static ResettableListIterator arrayListIterator ( Object [ ] array ) { } public static ResettableListIterator arrayListIterator ( Object array ) { } public static ResettableListIterator arrayListIterator ( Object [ ] array , int start ) { } public static ResettableListIterator arrayListIterator ( Object array , int start ) { } public static ResettableListIterator arrayListIterator ( Object [ ] array , int start , int end ) { } public static ResettableListIterator arrayListIterator ( Object array , int start , int end ) { } public static Iterator unmodifiableIterator ( Iterator iterator ) { } public static ListIterator unmodifiableListIterator ( ListIterator listIterator ) { } public static MapIterator unmodifiableMapIterator ( MapIterator mapIterator ) { } public static Iterator chainedIterator ( Iterator iterator1 , Iterator iterator2 ) { } public static Iterator chainedIterator ( Iterator [ ] iterators ) { } public static Iterator chainedIterator ( Collection iterators ) { } public static Iterator collatedIterator ( Comparator comparator , Iterator iterator1 , Iterator iterator2 ) { } public static Iterator collatedIterator ( Comparator comparator , Iterator [ ] iterators ) { } public static Iterator collatedIterator ( Comparator comparator , Collection iterators ) { } public static Iterator objectGraphIterator ( Object root , Transformer transformer ) { } public static Iterator transformedIterator ( Iterator iterator , Transformer transform ) { } public static Iterator filteredIterator ( Iterator iterator , Predicate predicate ) { } public static ListIterator filteredListIterator ( ListIterator listIterator , Predicate predicate ) { } public static ResettableIterator loopingIterator ( Collection coll ) { } <START_BUG> public static ResettableIterator loopingListIterator ( List list ) { <END_BUG> if ( list == null ) { throw new NullPointerException ( "List<seq2seq4repair_space>must<seq2seq4repair_space>not<seq2seq4repair_space>be<seq2seq4repair_space>null" ) ; } return new LoopingListIterator ( list ) ; } public static Iterator asIterator ( Enumeration enumeration ) { } public static Iterator asIterator ( Enumeration enumeration , Collection removeCollection ) { } public static Enumeration asEnumeration ( Iterator iterator ) { } public static ListIterator toListIterator ( Iterator iterator ) { } public static Object [ ] toArray ( Iterator iterator ) { } public static Object [ ] toArray ( Iterator iterator , Class arrayClass ) { } public static List toList ( Iterator iterator ) { } public static List toList ( Iterator iterator , int estimatedSize ) { } public static Iterator getIterator ( Object obj ) { } }

Fix:
public static ResettableListIterator loopingListIterator ( List list ) {